To register at this property, guests who are Indian citizens must provide a valid photo identity card issued by the Government of India. PAN cards are not accepted. Travelers who are not citizens of India must present a valid passport and visa.
I booked with hotels.com also got a confirmation number . Had a long flight from london to mumbai by the time we got to the hotel was around 16 hours , got there at 0015 in the morning and was told there no booking I showed him the confirmation number but he was not interested. Had to book another room , first time I ever experienced this with Hotels.com also emailed them but not a great response been such a big company .